Fluxon dynamics by microwave surface resistance measurements in MgB2
arXiv:cond-mat/0309654 · doi:10.1016/j.physc.2003.09.103
Abstract
Field-induced variations of the microwave surface resistance, Rs(H), have been investigated in high-density ceramic MgB2. At low temperatures, several peculiarities of the Rs(H) curves cannot be justified in the framework of models reported in the literature. We suggest that they are ascribable to the unconventional vortex structure in MgB2, related to the presence of two gaps. On the contrary, the results near Tc can be accounted for by the Coffey and Clem model, with fluxons moving in the flux-flow regime, provided that the anisotropy of the upper critical field is taken into due account.
arXiv comment6 pages, 4 figures
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Cited by in corpus (3)
- Depinning frequency in a heavily neutron-irradiated MgB2 sample
- Microwave surface resistance of pristine and neutron-irradiated MgB2 samples in magnetic field
- Field-induced suppression of the pi-band superconductivity and magnetic hysteresis in the microwave surface resistance of MgB_2 at temperatures near T_c